Thermal motor.



G. A. ANDERSON.

THERMAL MOTOR.

APPLICATION FILED JUNE 8, 1912.

1,055,439. Patented Mar. 11 1913.

CHARLES A. ANDERSON, OF CHICAGO, ILLINOIS.

THERMAL MOTOR.

Specification of Letters Patent.

Patented Mar.11,1913.

Application flled June 8, 1912. Serial No. 702,554.

To all whom it may concern:

Be it known that I, CHARLES A. ANDER- son, a citizen of the United States, residing at Chicago, in the county of Cook and State of Illinois, have invented certain new and useful Improvements in Thermal Motors, of which the following is a specification.

My invention relates to motors of that general type wherein the motive effect is pro duced through the agency of successive variations in temperature imparted to a metal member to cause alternate expanding and contracting or contracting and expanding movements of the latter.

The principle of my invention can be carried out through the creation in a local region of variations either above or below,

, surrounding temperature.

I have herein illustrated my invention as taking the form of a toy balance; but the princlple is capable of embodiment in a great variety of different forms as well as application to a considerable variety of dif-. ferent uses.

Referring to the accompanying drawings, Figure 1 is a side elevational view and Fig. 2 is a front elevational view of the form of the invention designed to operate through the application of heat, or a rise above normal temperature, in the local region. Fig. 3 is a side-elevational view of a form of the invention designed to operate through the application of cold, or a fall below normal temperature in the local region. Fig. 4 is an enlarged fragmentary detail of the laminated balance-bar used in the embodiment of the invention illustrated in Figs. 1 and 2. Fig. 5 is a view similar to Fig. 4 of a fragment of the laminated balance-bar used in the embodiment of the invention shown in Fig. 3. Fig.6 is an enlarged de-.

tail view in cross section through one of the bearings of the balance-bar.

.On knife-edge bearings 14" a pendulum rod by hangers 12 a pair of bear- 14. Secured to the lower end of said pendulum rod, as by soldering or otherwise, is the balance-bar which, as shown in Fig. 4, is a laminated structure comprisin two metal strips of unequal coefficients of inear expansion soldered together, one of said strips being designated by 15 and the other by 16.

This balance-bar is formed with a pair of integral 100 s 17 approximately centrally thereof and coated on opposite sides of the pendulum rod 14. On the outer ends of the balance-bar are preferably mounted equal balanced weights, herein shown as dummy" figures 18. Supported near the base of the upright 11 is a shallow pan or holder 19 containing a concave mirror 20, the focal point of which lies mid-way between the loops 17 of the balance-bar when the latter is in neutral or balanced position. In the operation of this form of the invention, the device is so positioned with reference to the suns rays, or the rays from any other source of heat, that the latter are caught by the mirror 20 and focused at a point, as stated, mid-way between the loops 17 of the balance-bar. In the balance-bar shown in Figs. 1, 2 and 4 the lower metal strip 16 is the more sensitive, or possessed of the higher coeflicient of linear expansion. By starting the figures 18 and the balance-bar in a rocking or see-saw motion by the finger, the loops 17 are alternately brought into the focus of the heat rays from the mirror 20, thereby suddenly expanding the two metal layers of the balance-bar unequally, the inner layer of the coil being expanded more than the outer layer. and thereby throws the weight 18 at the end of the arm containing the loop thus afi'ectecl upwardly or toward the center and destroys the previously balanced condition of the two weights, thus causing the pendulum, balancebar and weights to begin a swinging motion. In this way the pendulum and the suspended balance-bar and weights are caused to swing back and forth continuously so long as the action of the heat-ray on the loops 17 is maintained.

In the form of the invention illustrated in Figs. 3 and 5, I produce the same effect by causing the loops 17' to be alternately This expands the coil affected by decreases in the normal tempera- Q I 17 1,oss,4so, 1 1

of upstanding metal lugs'22' sopositioned that the loops 17- of thebalanoe-bar, as the latter swings, alternately move to positions between them. vThe major-portion of the cylinder 21 is wrapped with a moisturebsorbent material, such as any suitable cloth 23, which is saturated by water, alcohol,

'gasolene, or anymore or less volatile liquid.

The evaporation of this moisture is, of course,-attended by a lowering of the-temperature of the cylinder 21 andits lugs 22 below the normal temperature obtaining in the room or other place where the device happens to be. In this form .of the, invention the more sensitive metal '16 or that having the higher .coeflicient. of expansion. constitutes the upper layer of the balancebar and the outer layer of the loops17' since the disturbance of the balance is, 'in this.

case, produced by the 1 greater contracting movement of the more sensitive metal 16, as the coil swings into or across the region of abnormal cold between the two lugs 22. In this form of the invention, the cylinder coat-' ing need be moistened only at very considerable intervals to keep the device continu- 'ously running.

twov arms of zontallyor do nwardly from the loops, instead of v upwardly, as shown, the described It will be olgious' that, in where the relative? arrangement of thestrips of the balance-bar would be simply reversed, since in suchc'ases the contracting'action of the loops 17 and 17 would alternately disturb the balanced condition of the weights by throwingthe latter inwardly orrtoward the axis f suspension, precisely asoccurs in the device shown and described under the expanding-action of the loops. f

From the foregoing it will be seen that the principle of the invention comprehends the j creation of a' local region of abnormal temperature (and bythe expression"? abnormal temperature Imean 'a temperature either above or below the mean ,or' normal temperature prevailing in the locality where the device hapgens to be) in association with a suspende' balance in which is formed a readily expansible orcontractible part that, under the swinging or rocking movement of the balance moves into or across such local region of abnormal temperature and by-its distortion destroys the equilibrium of the balance. i In its chief intended application, the principle of my invention is designed to be lemgloyed as an advertising novelty for window isplay to, attract attention, owing to the apparent mystery involved in the cause of sustained 'movement'of the balanced figures;

, although the device-constitutes also a clever means for changing the temperature locally the balance-bar extend horiof a balance-barmade, of two strips of metal and attractive toy to interest and amuse l, children.

I. claim- 1. In a thermal motor, members .movably mounted in approximate equilibrium, a thermostatic member opera ively associated with said movably .mounte ,members, and

in the vicinity of said thermostatic member. 2. In a .thermal motor, a thermostatic member comprising two parts having difierent coeflicients of expansion and united to. warp the member on change of temperature, a pivotal support, weights shift-able toward and from said pivotal support by warping of said thermostatic member, and means for producingya localized change in temperature in the vicinity of. said thermostatic member. 1 3. In a thermal motor,the combination of a balance-bar having formed therein between its ends an expansible, or contractible loop, means for pivotally supporting said balance-bar between its ends, and means for creating a local region of abnormal temperature into and out of which the loop ofsaid balance-bar passes as the latter oscillates. I 4. In a thermal motor, the combination of a balance-bar having formed therein between its ends an cxpansible or contractible loop, means for pivotally supporting said balance-bar between its ends, balanced weights; on the opposite ends of said balance-bar, and means for creating a local region of abnormal temperature into and out of which the loop of said balance-bar passes as the latter oscillates.

5. In a thermal motor, the combination having unequal coeflicients 'of expansion formed with a loop intermediate its ends, means for pivotally supporting said balancebar between its ends, balanced weights on the opposite ends of said balance-bar, and means for creating a local region of abnormal temperature into and out of which the loop of said balance-bar passes as the latter oscillates. i

6. In a thermal motor, the combination of a balance-bar made of two strips of metal having unequal coefficients of expansion formedwith a pair of loops intermediate its ends, means forpivotall supportin said balance-bar between sai loops, ba anced weights on the ends of said balance-bar, and means for creatingga local region of abnor-' mal temperature into and'out of which the loops of said balance-bar alternately passes the latter oscillates. I CHARLES A. ANDERSON. Witnesses:

SAMUEL N. Pom), -EDMUND G. INGERSOLL. 

